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Regex - Should hyphens be escaped? [duplicate]
...er in the range (e.g. [-a-z] or [0-9-]), OR escape it (e.g. [a-z\-0-9]) in order to add "hyphen" to your class.
It's more common to find a hyphen placed first or last within a character class, but by no means will you be lynched by hordes of furious neckbeards for choosing to escape it instead.
(A...
Maintain the aspect ratio of a div with CSS
...s:
.demoWrapper {
padding: 10px;
background: white;
box-sizing: border-box;
resize: horizontal;
border: 1px dashed;
overflow: auto;
max-width: 100%;
height: calc(100vh - 16px);
}
div {
width: 100%;
padding-bottom: 75%;
background: gold; /** <-- For the demo **/
}
<d...
@ variables in Ruby on Rails
...silent dup of variable, or making it 'const' so that it can't be modified, etc)? I'm coming from a C/C++ & Java perspective, and the really vague and optional syntax is driving me nuts!
– Dan Devine
Jun 13 '18 at 18:05
...
List columns with indexes in PostgreSQL
...um = ANY(ix.indkey)
and t.relkind = 'r'
and t.relname like 'test%'
order by
t.relname,
i.relname;
table_name | index_name | column_name
------------+------------+-------------
test | pk_test | a
test | pk_test | b
test2 | uk_test2 | b
test2 | uk_te...
nginx: [emerg] could not build the server_names_hash, you should increase server_names_hash_bucket_s
...hash_bucket_size 64;
at the top of your http block (probably located in /etc/nginx/nginx.conf). I quote from the nginx documentation what to do when this error appears: In this case, the directive value should be increased to the next power of two. So in your case it should become 64.
If you still...
Two divs, one fixed width, the other, the rest
...;/div>
CSS:
.left {
overflow: hidden;
min-height: 50px;
border: 2px dashed #f0f;
}
.right {
float: right;
width: 250px;
min-height: 50px;
margin-left: 10px;
border: 2px dashed #00f;
}
You can also do it with display: table, which is usually a better approac...
MySQL DISTINCT on a GROUP_CONCAT()
...UP_CONCAT has DISTINCT attribute:
SELECT GROUP_CONCAT(DISTINCT categories ORDER BY categories ASC SEPARATOR ' ') FROM table
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Rails - Nested includes on Active Records?
...
how to add there a order?
– Florian Widtmann
Jan 12 '16 at 7:49
6
...
Big O, how do you calculate/approximate it?
... // 3
}
}
The first thing you needed to be asked is the order of execution of foo(). While the usual is to be O(1), you need to ask your professors about it. O(1) means (almost, mostly) constant C, independent of the size N.
The for statement on the sentence number one is tricky....
Error Code: 2013. Lost connection to MySQL server during query
...
Add the following into /etc/mysql/cnf file:
innodb_buffer_pool_size = 64M
example:
key_buffer = 16M
max_allowed_packet = 16M
thread_stack = 192K
thread_cache_size = 8
innodb_buffer_pool_size = 64M
...